The present invention is particularly directed to an apparatus for making a laminated web having spaced removable elements such as labels affixed to a base liner and to the method thereof.
Labels and other similar flexible elements are widely used for purposes of identification, information, display and other purposes. A sticky label-like element is often used for application in the production of packaged products and are otherwise sold to end users including retail consumers. In the process of manufacture, a laminated web including a base carrier or liner and a laminated layer of the label-like element material is formed. The laminated web is then passed through a forming line which will generally includes a supply at which a roll or other supply of the laminated web of indefinitive length is located. The web is passed from the supply through a die cutting machine and a trim removal machine which may be formed as a single integrated apparatus to provide the laminated web with the liner carrying the severed and separated elements. The web may then be passed through a label applying machine for application of the label to a suitable container such as a bottle, box or other member, or rewound into a suitable roll in a rewind apparatus. In a conventional system, draw rolls are coupled to the downstream portion of the laminated web and particularly the liner and pull the laminated web through the various machines in the line. The web is maintained under an appropriate tension to provide proper timed movement of the laminated web through the various devices or machines to establish accurate forming and location of the removble elements. Such apparatus is well known and widely used in the packaging, labeling of products and manufacture of products. The die cutting apparatus often includes a reciprocating or rotating die which provides repetitive precise cutting of the outer label layer. As a practical matter, the die cutting apparatus may, at times, move through the removable element material and actually nick the liner, thereby creating a weak spot in the liner. With the event of high speed processing lines, the tension on the web is such that the nicked liner may be so weakened as to break as the laminated web is passed down through the line. Breakage of the web results in the necessity for complete shut down of the line, the removal of the broken web and rethreading of the laminated web through the line from the supply to the rewind apparatus. This is time consuming and results in a significant loss as well as inconvenience in production.
The prior art has recognized the problem associated with a damaged liner. U.S. Pat. No. 3,574,026 which issued Apr. 6, 1971 particularly discusses the problem and notes the difficulties generated by a nicked and thereby weakened liner. The patent discloses a method of separating the laminated web, forming the cut and then reassembling the laminated web. This requires special complex apparatus for both separating and cutting the label or element layer of the laminated.
The prior art apparatus can be conveniently placed in a standard label forming line or the like which includes the usual rotary die cutting machine.
There is a need therefore for a cost-effective apparatus for processing a continuous laminated web with a cut outer layer and a liner in which to detect a potential break in the liner and provide appropriate apparatus to remove the weakened portion from the web so as to permit the continuous high speed processing.